* {
    margin: 0;
    padding: 0;
}
.w {
    width: 1200px;
    margin: auto;
}
body {
    background-color: #f3f5f7;
}
li {
    list-style: none;
}
a {
    text-decoration: none;
}
/* 清除浮动 */
/* .clearfix:before,.clearfix:after {
    content:"";
    display:table; 
  }
  .clearfix:after {
    clear:both;
  }
  .clearfix {
     *zoom :1;
  }    */
 
.header {
    height: 42px;
    /* background-color: pink; */
    /* 注意此地方会层叠 w 里面的margin */
    margin: 30px auto;
}
.logo {
    float: left;
    width: 198px;
    height: 42px;
}
.nav {
    float: left;
    margin-left: 60px;
}
.nav ul li {
    float: left;
    margin: 0 15px;
}
.nav ul li a {
    display: block;
    height: 42px;
    padding: 0 10px;
    line-height: 42px;
    font-size: 18px;
    color: #050505;   
}
.nav ul li a:hover {
    border-bottom: 2px solid #00a4ff;
    color: #00a4ff;
}
/* search搜索模块 */
.search {
    float: left;
    width: 412px;
    height: 42px;
    margin-left: 70px;
}
.search input {
    float: left;
    width: 345px;
    height: 40px;
    border: 1px solid #00a4ff;
    border-right: 0;
    color: #bfbfbf;
    font-size: 14px;
    padding-left: 15px;
}
.search button {
    float: left;
    width: 50px;
    height: 42px;
    /* 按钮button默认有个边框需要我们手动去掉 */
    border: 0;
    background: url(images/btn.png);
}
.user {
    float: right;
    line-height: 42px;
    margin-right: 30px;
    font-size: 14px;
    color: #666;
}
/* banner区域 */
.banner {
    height: 421px;
    background-color: #1c036c;
}
.banner .w {
    height: 421px;
    background: url(images/banner2_20190819_210028.png) no-repeat top center;
}
.subnav {
    float: left;
    width: 190px;
    height: 421px;
    background: rgba(0,0,0, 0.3);
}
.subnav ul li {
    height: 45px;
    line-height: 45px;
    padding: 0 20px;
}
.subnav ul li a {
    font-size: 14px;
    color: #fff;
}
.subnav ul li a span {
    float: right;
}
.subnav ul li a:hover {
    color: #00a4ff;
}
/* 课程表模块 */
/* 父级元素 */
.course{
    float: right;
    width: 230px;
    height: 300px;
    background-color: #fff;
    /* 浮动的盒子不会有塌陷的问题 */
    margin-top: 50px;
}
/* 子级元素 */
.course h2{
    height: 48px;
    background-color: #9bceea;
    font-size: 18px;
    color: white;
    line-height: 48px;
    text-align: center;
}
.course .db{
    padding: 0 20px;
}
.db ul li{
border-bottom: 1px solid lightslategray;
padding: 10px 0;
}
.course .db ul li h4{
    font-size: 16px;
    color: #666666;
}
.db ul li p{
    font-size: 12px;
    color: lightslategray;
    margin-top: 5px;
}
.db .more{
    display: block;
    height: 38px;
    border: 2px solid #00a4ff;
    margin-top: 5px;
    color: #00a4ff;;
    line-height: 38px;
    text-align: center;
    font-size: 16px;
    font-weight: 700;
}
/* 精品推荐模块 */
.goods {
    /* 行高会继承给子元素 */
    line-height: 60px;
    height: 60px;
    background-color: #fff;
    margin-top: 10px;
    box-shadow: 0 2px 3px 3px rgba(0,0,0, 0.1);
}
/* 使用内边距magin撑开盒子，盒子大小不变 */
.goods h3{
    float: left;
    color: #00a4ff;
    margin-left:30px; 
}
.goods ul{
    float: left;
}
.goods ul{
    margin-left: 30px;
}
.goods ul li{
    float: left;
}
.goods ul li a{
    padding:0 30px;
    border-left:1px solid #ccc;
    font-size: 16px;
    color: #050505; 
}
.mod{
    float: right;
    color: #00a4ff;
    margin-right: 30px;
}
/* box核心模块 */
.box{
    margin-top: 30px;
    /* 清除浮动：父级使用浮动，不方便给高度，影响下面的标准流， */
    overflow: hidden;
}
.box .box-hd{
    height: 45px;
}
.box h4{
    float: left;
    color: #494949;
    font-size: 20px;
}
.box a{
    float: right;
    color: #a5a5a5;
    font-size: 12px;
    margin-top: 10px;
    margin-right: 30px;
}
.box-bd ul{
    width: 1225px;
}
.box-bd ul li{
    /* 子绝父相 */
    position: relative;
    float: left;
    width: 228px;
    height: 270px;
    background-color:#fff;
    margin-right:15px;
    margin-bottom: 15px;
}
.box-bd ul li>img{
    width: 100%;
}
.box-bd ul li em{
    /* 绝对定位 */
    position: absolute;
    top:4px;
    right: -4PX;
}
.box-bd ul li h4{
    margin: 20px 20px 20px 25px;
    font-size: 14px;
    color: #050505;
    font-weight: 400;
}
.box-bd .info{
    margin: 0 20px 0 25px;
    font-size: 12px;
    color: #999;
}
.box-bd .info span{
    color: #ff7c2d;
}
/* footer模块 */
.footer{
    /* clear: both; */
    height:415px;
    background-color: #fff;
}
.footer .w{
    padding-top:35px; 
}
.footer .copyright{
    float: left;
}
.footer img{
    padding: 20px 0;
}
.footer p{
    font-size: 14px;
    color: #666666;
    padding-bottom: 20px;
}
.footer .app{
    display: inline-block;
    width: 118px;
    height: 33px;
    border: 2px solid #00a4ff;
    color: #00a4ff;
    line-height: 33px;
    text-align: center;
    font-size: 16px;
}
.footer .links{
    float: right;
}
.links dl{
    float: left;
    margin-left: 100px;
}
.links dl dt{
font-size: 16px;
color: #333;
margin-bottom: 10px;
}
.links dl dd a{
    color: #333;
    font-size: 12px;
}

